LIBS is a spectroscopic analysis technique in which a laser pulse vaporizes ng to μg quantities of material and thermally excites the vaporized material in a short-lived plasma (˜8000 K). Light emitted from atoms, ions, and simple molecules in the plasma is collected and analyzed. LIBS may be utilized for elemental analysis to determine the composition of the target material via unique element fingerprint spectra, i.e., by observing specific spectral emission lines characteristic of light emitted from a sample that correspond to particular elements.
LIBS may be extended from identification of individual elements to identification of materials such as metals, chemical substances, pathogens, and explosives. In these cases, the shape of the LIBS spectral data may be used for identification of materials as opposed to particular elemental lines. The spectral data generally include multiple elemental and background emissions over an observed range of wavelengths. The spectral data may be collected from a LIBS instrument and input to an algorithm for identification. However, such algorithms are difficult to develop because the algorithms must differentiate relatively complex spectral data, which may include data derived information pulled from the spectra.
Accordingly, a need exists for alternative methods for forming recognition algorithms for identifying materials with LIBS.